This is how you should dress this winter, according to J. Crew's head of men's design

For a long time—most of the history of menswear, in fact—we st rived for harmony in the way we dressed. Every element of any given outfit aligned with the others. Think topcoats with business suits, or waxed cotton jackets with heavy country tweeds. There was a vibe, and each portion of the whole contributed to it. It made sense. But it was also kind of boring.

Because now, we understand what happens when we give harmony the boot and aim for a little push-and-pull. We throw disparate and sometimes unexpected items into the mix and shake it around to see what we can make. And that is far from boring. In fact, it's pretty damn exciting.

There is, of course, the mash-up of traditional tailoring and performance wear that's been going strong for a few seasons now. "I always like that tension of putting something technical over something a little more rustic like wool," says Frank Muytjens, the man behind J. Crew's men's designs. "So if you wear a suit, you can throw a waterproof parka over it. I think that's amazing."

To that end, J. Crew works with renowned woolen mills like Moon and Harris Tweed—"we love their story and heritage, and we know the product just doesn't get any better"—for its in-house tailored clothing, as well as specialty outdoors brands like The North Face for collaborative outerwear pieces. According to Muytjens, you should wear them together. You can also pair a topcoat with technical items like a fleece windbreaker or his favorite, a down vest.

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But if you've already given that sort of thing a shot and want to try your hand at a new move, Muytjens recommends something a little more advanced: playing with fit. It's might seem scary, given menswear's obsession with all-slim-everything over the past few years, but, as he explains, "Your eye always adjusts itself season by season. One season you look at a windbreaker and it's just a windbreaker, and the next season it's different and exciting because you see it in a different way."

That's what's happening right now with the introduction of more relaxed silhouettes, especially in outerwear. "I love seeing the proportions change again," says Muytjens. "Not that slim is going to go away, but [oversized clothing] is something a guy can add to his wardrobe. And I think a skinny jean goes great with a slouchy, oversized topcoat." If you'd rather stay trim up top, a tailored jacket with a wider-leg trouser is also a good move.

This new approach doesn't mean you can start wearing things that aren't your size. "Even if it's slouchy, it should still fit the right way," the designer notes.

This is menswear, after all. Things shift, but not radically. Which is exactly how Muytjens likes it: "So it's always changing and evolving—changing colors or proportions or fabrications—and that's what I love about menswear. You design within a given frame, and then it's up to you to change everything within that frame."